firmware: qcom: uefisecapp: fix efivars registration race

firmware: qcom: uefisecapp: fix efivars registration race

commit da8d493a80993972c427002684d0742560f3be4a upstream.

Since the conversion to using the TZ allocator, the efivars service is
registered before the memory pool has been allocated, something which
can lead to a NULL-pointer dereference in case of a racing EFI variable
access.

Make sure that all resources have been set up before registering the
efivars.

Fixes: 6612103ec35a ("firmware: qcom: qseecom: convert to using the TZ allocator")
Cc: stable@vger.kernel.org	# 6.11
Cc: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250120151000.13870-1-johan+linaro@kernel.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>